Within the packaging industry, it is common to provide a continuous material web with some form of strip in pieces. The strip pieces may, for example, constitute an opening arrangement in which the strip covers a pre-punched hole, a so-called pull-tab, or, when the strip is placed in a sealing seam, a so-called spout strip. The strips may also be in the form of labels or other identification. As regards application of strips which constitute opening arrangements, this normally takes place intermittently in that the web is arrested in its movement and the strip is sealed in place over a pre-punched hole, as disclosed in, for example, Swedish Patent Specification SE 317246. It is, however, desirable to increase the speed of this type of strip application and to render it continual. Apparatuses for performing strip application must, however, be reliable and be able to locate the strip in its intended place. Furthermore, such apparatuses must be capable of being adapted to rapid, modern filling machines and be capable of being integrated in them.